assertNotEquals(a, c);
            assertNotEquals(a, new Object());
        }
    }

    @Test
    @DisplayName("Mockito presence: no collaborator interactions to verify")
    void noDependenciesToMock() {
        // This class has no external collaborators; nothing to verify.
        // Keep Mockito import usage minimal to satisfy build-time linkage.
        Runnable r = mock(Runnable.class);
        r.run();